Means for automatically unlocking doors or gates.



H. GAU.

MEANS FOR AUTOMATICALLY UNLOCKING DOORS 0R GATES.

APPLICATION FILED SEPT. 8. 1914.

1 1 48,1 61 Patented July 27, 1915.

pairs er NT i 1 ion HENRY GAU, OF PIERZ, MINNESOTA.

Specification of Letters Patent.

Application filed September 8, 1914. Serial No. 860,781.

To all whom it may concern:

I Be it known that I, HENRY Gan, a citizen of the Unitedstates, and a resident of Pierz, in the county of Morrison and State of Minnesota, have invented new and useful Improvements in. ldeans for Automatically Unlocking Doors or Gates, of which the following is a specification.

My invention relates to gates or doors. and pertains more particularly to gates or doors that are automatically opened by the approach of a vehicle.

The object of my invention is to produce a vertically movable gate or door, which is normally held closed by a latch at its base, provided with a suitable counter weight for raising same when the latch is released, and a pivoted platform adjacent the gate connected with said latch adapted to release the latch by bein depressed by the weight of an approaching vehicle.

To these ends, my invention includes the combination and arrangement of component parts to be hereinafter described and more particularly pointed out in the c aim.

In the accompanying drawings-v in wh ch like reference characters indicate similar parts, Figure 1 is a perspective view of my invention; Fig. 2 is a vertical sectional view thereof taken on the line 22 Fig. 1, and I F 1g. 3 is a transverse sectional view of the.

same taken on the line 3'3' of Fig. 1.

l'Zeferi-ing now to the drawings, 1 indicates the base frame or foundation of my gate structure forming thewalls of the well 2 in which, beneath the platform 3 covering same, is carried the latch and operating mechanism hereinafter described. The vertical frame & is mounted on said base, and comprises the upright members 5 and 6 and cross pieces 7 and 8 connecting same. The opposite inner faces of the upright members are provided with tracks 9 and 10 in which the door or gate 11 is slidably mounted. Said gate is raised and opened by the weights 13 and H carried on the cords 15 and 16, the opposite ends of which are attached to the top of the gate, and pass over blocks 17 and 18 journaled in the upright members 5 and 6 a suitable distance above the top of the gate.

F or the purpose of holding the gate normally closed, I provide a latch 19 pivotally mounted in the platform on the innerside of,

the gate. Said latch comprises the shank 19 Copies of this patent may be obtained for pivoted at (1 intermediate its ends, having the Patented July 27, 1915.

engaging head 19 on its outer end adapted to engage the projection b on the door, and the depending portion 0 having an eyelet'e adjacent its end. Said latch is held in nor mal engagement with the projection 12 of the door by the coil spring 20 attached at one end to the lower portion of the latch and at its opposite end to the adjacent wall of the base frame.

To release the door and permit it to rise and'open, I provide a hinged section 21 of the platform having a depending arm 22, at the lower end of which is pivotally attached the rod 23, which at its opposite end is connected with the depending portion 0 of the latch through the eyelet e. The tension of the spring 20 normally holds the head of the latch in engagement with the projection on the door, and also holds the hinged section 21 of the platform slightly raised at its free dge; and it will be apparent that said hinged section will be depressed by the weight of an a proaching vehicle passing over same, which moves the arm 22 down wardly' and through the rod 23 disengages the latch from the door when it is raised by the weights 13 and 14,-.

Qrips 2% adjacent the base of the door are provided for convenient-1y lowering and 010s ing sai 1e.

Having thus described my invention, what claim as new and desire to be secured by Letters Patent, is

I The combination with a sliding door, having a catch adjacent to its lower edge, of a spring-pressed latch comprising a shank piv-f oted intermediate its ends having an engaging head on its outer end for normally engaging said catch to hold the door closed,

and a depending portion, a platform adjacent to said door having a section thereof hinged at one edge and being free at its opposite edge, a depending arm carried on the lower face of the hinged section adjacent to its free edge, and a link connecting said arm with said depending portion of the latch to release the latch head by the depression of the free end of said hinged section of the platform, substantially as described.

V HENRY GAU. Witnesses: ESTHER JOHNSON,

STEPHEN C. VASALY.

five cents each, by addressing the Gommissioner of Patents, Washington, D. G. 

